Uniaxial tensile fatigue failure of concrete under constant-amplitude and programme loading

Synopsis Uniaxial repeated-tension and tension-compression tests on plain concrete are described. The results are presented as S—N diagrams and in the form of a modified Goodman diagram. Stress reversals appeared to reduce life significantly. By a statistical treatment, the influence of scatter in the static strength upon the fatigue results was ascertained. To avoid the effect of this scatter, cyclic creep rate was evaluated to predict life more accurately in constant-amplitude tests as well as in programme loading tests. With this procedure for programme loadings, no significant sequence effect of the loading blocks was observed in the resulting Miner sums. Miner's number M = 1 proved to be a safe failure criterion in general.